Category: water treatment

Towards zero liquid discharge desalination

March 25, 2020

Desalination processes that converts seawater into drinking water inevitably generates a high salt solution known as brine, which has to be discharged. Currently, the concentrated brine is typically discharged into the sea. However, concerns have arisen on the potential ecological impacts of the concentrated brine on marine life. Specifically, concentrated brine is known to affect … More Towards zero liquid discharge desalination

Chelating compounds in R2A agar might chelate chloramine compounds and help increase recovery of microbes from tap water

January 1, 2020

Low in nutritional content, R2A agar is the gold standard agar for recovering microbes from environmental samples such as tap water. However, observations of increased recovery of microorganisms from tap water on R2A agar relative to a formulated colourless agar pointed to possible presence of chelating compounds in R2A agar that help sequester chloramine disinfectant … More Chelating compounds in R2A agar might chelate chloramine compounds and help increase recovery of microbes from tap water

Difficulty in dislodging biofilms in drinking water pipelines

July 19, 2019

Aggregates of microbial cells would form on any surface in contact with water in a consortium known as biofilm. Architecturally complex with many layers, life in a biofilm provide many advantages to microbial cells such as protection from fluctuating environmental conditions and antimicrobial agents as well as provision of metabolites from symbiotic species. Hence, biofilms … More Difficulty in dislodging biofilms in drinking water pipelines

Reverse osmosis uses 90% less energy compared to thermo distillation methods in seawater desalination

December 6, 2018

Reverse osmosis uses high pressure to overcome the inherent osmotic pressure of freshwater to help remove salts from seawater. The process is energy intensive due to the need for high pressure. However, compared to thermo distillation methods for seawater desalination which uses heat induced evaporation of water to generate freshwater, reverse osmosis uses 90% less … More Reverse osmosis uses 90% less energy compared to thermo distillation methods in seawater desalination

Adsorptive membrane treatment technologies may not have a low energy footprint

November 22, 2017

Adsorption is a low energy water and wastewater treatment technology. Thus, would the combination of adsorption and membrane treatment technologies lead to a low energy treatment system? The answer depends on the pore size of the membrane used in adsorptive membrane technologies, where the membrane surface serves as adsorbent for the sorption of heavy metals … More Adsorptive membrane treatment technologies may not have a low energy footprint

Energy requirement of forward osmosis membrane processes may not be lower than that of reverse osmosis

November 18, 2017

Forward osmosis is a relatively new membrane process for wastewater treatment. Specifically, it entails the addition of a volatile solute (such as ammonium carbonate) to the permeate side of the membrane for inducing the diffusion of water molecules across the membrane down a water concentration gradient. The volatile solute would be subsequently removed from the … More Energy requirement of forward osmosis membrane processes may not be lower than that of reverse osmosis

Conventional drinking water treatment

September 1, 2017

All over the world, drinking water treatment comprises a specific set of steps designed to progressively remove various types of contaminants. Specifically, drinking water treatment comprises sedimentation, coagulation, filtration, sedimentation and disinfection.   When raw water first arrives at a drinking water treatment plant, it typically carries a heavy load of particles and is muddy … More Conventional drinking water treatment

Conventional drinking water treatment

September 1, 2017

All over the world, drinking water treatment comprises a specific set of steps designed to progressively remove various types of contaminants. Specifically, drinking water treatment comprises sedimentation, coagulation, filtration, sedimentation and disinfection. When raw water first arrives at a drinking water treatment plant, it typically carries a heavy load of particles and is muddy in … More Conventional drinking water treatment

Reverse osmosis is the only means for removing trace contaminants in water

August 8, 2017

Current drinking water treatment techniques, while effective, is increasingly unable to cope with the larger set of trace contaminants in treated water found to impact on human health. For example, in some areas of the world, treated water contains trace concentration of lead (~ 3 parts per billion, ppb level), arsenic (~ 2 ppb), boron, … More Reverse osmosis is the only means for removing trace contaminants in water

Taste of pure water produced through reverse osmosis

August 7, 2017

Reverse osmosis is increasingly used for desalination and purifying water unable to be treated by other means for removing trace contaminants known to impact on human health. However, what is the taste of pure water produced by reverse osmosis?   The answer is it is different from tap water. Specifically, Singapore uses reverse osmosis for … More Taste of pure water produced through reverse osmosis